The invention relates to heat-sealable, laminated packages for hermetically sealing an object therein and, in particular, to such a package having means for facilitating manual tearing of the package.
Packages constructed from flexible, laminated materials are well known. Many types of objects are hermetically sealed in laminated packages to preserve their freshness. Such a package is described in U.S. Pat. No. 4,139,643. The package comprises a three-ply laminated pouch. At column 2, starting at line 39, the laminate is described as preferably consisting of an outer ply of polypropylene or polyester, a central ply of aluminum foil and an inner ply of any suitable, heat-sealable thermal plastic material. Starting at column 3, line 20, the package is described as having transverse parallel lines of weakness formed across one of the heat seals.
Another laminated package is described in U.S. Pat. No. 4,279,344. The package is described as including three layers. As with the package of the earlier patent, the package is described starting at column 2, line 29, as having an outer layer formed of a plastics resin material, a central structural barrier layer formed of a metallic foil, such as aluminum foil, and an inner layer formed of a suitable heat-sealable material. Suitable heat-sealable layers are described starting at column 2, line 58 to include a polypropylene or a polyethylene-polypropylene copolymer blended with an ionomer resin. The package is described as openable by peeling apart two of the lamina along the heat seal.